Centrifugal pump

ABSTRACT

A centrifugal pump having front and rear apertures each of a size to permit removal of the impeller and the shaft seal therethrough. The rear cover assembly provides a support for the shaft seal housing and can be removed through either aperture.

United States Patent References Cited UNITED STATES PATENTS 9/1929 Hauseet a1. 8/1959 Anderson et 11 3/1961 Jassniker 3/1963 Lipe et al 10/1966Ruppet a1. 3/1970 Eberhardt Primary Examiner-Henry F. RaduazoAttorneysJohn P. Hines, Robert B. Benson and Arthur M.

Streich ABSTRACT: A centrifugal pump having front and rear apertureseach of a size to permit removal of the impeller and the shaft sealtherethrough. The rear cover assembly provides a support for the shaftseal housing and can be removed through either aperture.

CENTRIFUGAL PUMP I more particularly to an in-line centrifugal pumphaving means to remove the pump impeller and shaft seal from either endof the pump casing.

ln-line centrifugal pumps have aligned inlet and discharge nozzles whichare connected to the process fluid conduit line. It is desirable thatprovision be made to permit adjustment or replacement of wearing partswithin the pump casing without disturbing the connection of the pump tothe fluid line. Depending on the space available these adjustments orreplacements may be more easily accomplished either from the top orbottom of the pump casing in those applications where the pump isvertically mounted. In some instances the drive motor is supported bythe pump casing which further complicates the ease of repair andreplacement of the internal working parts of the pump.

It is therefore the intention and general object of this invention toprovide an in-line centrifugal pump with means to permit the easyremoval of the impeller from either end of the pump casing.

An additional object of the subject invention is to provide an in-linecentrifugal pump wherein one end cover for the pump casing supports thedrive shaft seal housing and which can be removed from either end of thepump casing.

These and other object of the subject invention will become more fullyapparent as the following description is read in light of the attacheddrawing which shows a centrifugal pump in cross section with attacheddrive motor constructed in accordance with the invention.

Referring to the drawing, the centrifugal pump of the subject inventioncomprises a pump casing generally designated 6 having an inlet nozzle 7and a discharge nozzle 8. For purposes of illustration only the pump isherein shown vertically mounted. Each of the nozzles 7 and 8 areprovided with mounting flanges 9 and 11, respectively, for connection'toa process fluid line. The pump casing 6 defines top and bottom apertures12 and 13, respectively. A suction cover 14 is releaseably connected tothe pump casing 6 in any conventional manner such as by studs 16 andnuts 17 to close the bottom aperture 13. The suction cover 14 defines apassageway which connects the inlet nozzle 7 with the eye of theimpeller 18.

The top aperture 12 is closed by means of a top cover assembly generallydesignated 19. This top cover assembly 19 is comprised of a top coverplate 21 which closes the aperture 12 and an annular axially extendingseal housing 22 in which is contained a mechanical seal generallydesignated 23. The top cover assembly is supported to the pump casing 6in a manner to permit removal thereof with the attached seal housing 22through the bottom aperture 13 after the suction cover 14 is removed.This is accomplished by providing a plurality of circumferentiallyspaced studs nd nuts 24 in the outer surface of the cover plate 21.These studs pass through a ring 26 which is supported in an annulargroove 27 provided in the upper outer surface of the pump casing 6. Thering 26 is maintained in position by means of a spacer housing generallydesignated 28 which is provided with a groove 29 which seats on theupper surface of the rig 26. The spacer housing 28 is connected to thepump casing 6 by means of circumferentially spaced studs and nuts 31. Itshould be understood that the ring 26 could be made an integral part ofthe spacer housing and the spacer housing could be an integral part ofthe motor housing without departing from the spirit of the invention.Pump drive means shown herein as an electric motor 32 is connected tothe spacer housing 28 by means of mounting bolts 33. The motor driveshaft 34 extends through the seal housing 22 and the upper cover plate21 into the interior of the pump casing 6. The impeller 18 is removablyconnected to the end of the drive shaft 34 in any conventional mannersuch as by the threaded connection shown herein for purposes ofillustration.

The mechanical seal 23 is adjusted by means of the stud and nut 35 andthis also provides a fastening means in conjunction with the stud 24between the cover assembly 19 and the motor 32.

With the above-described structure it can be seen that the pump impeller18 and the seal housing 22 can be easily removed through the front orlower portion of the pump casing. This is accomplished removing thesuction cover 14 from the bottom of the casing 6 and unscrewing theimpeller 18 from the end of the drive shaft 34. The nuts are thenremoved from the studs 24 permitting removal of the top cover assembly19 with the seal housing 22 through the lower aperture 13.

If it is impossible due to a lack of sufficient space to remove theimpeller and seal housing through the lower portion of the pump casing,it is possible to remove the motor and pump impeller with the shaft sealthrough the top of the pump casing. This is accomplished by merelyremoving the nuts from the studs 31 and lifting the motor upwardremoving the impeller and the cover assembly 19 therewith.

From the above it can be seen that a simplified inexpensive pumpstructure has been described. With this arrangement, means are providedto mount the motor on the pump casing and to remove the pump impellerand shaft seal either from the lower portion of the pump casing or fromthe upper portion of the pump casing.

The embodiments of the invention in which an exclusive property orprivilege is claimed are defined as follows:

1. The combination comprising: a pump casing defining a pumping chamberhaving an impeller positioned for rotation about an axis within saidchamber, said casing having a pair of axially aligned apertures openingto the exterior of said casing on opposite sides of said impeller andeach being of a size to permit removal of said impeller therethrough; aninlet and an outlet opening into said pumping chamber; a suction coverreleasably attached to said casing and closing one of said apertures; acover assembly closing the other of said apertures and both of saidapertures being of a diameter to permit passage therethrough of saidassembly; walls defining a shaft opening through said cover assembly;shaft sealing means connected to said cover assembly, aid sealing meansbeing of a size to permit passage thereof through said apertures; adrive shaft extending through said shaft opening and said shaft sealingmeans; means releasably connecting said pump impeller to said shaft forrotation therewith; and fastening means releasably supporting said coverassembly to said pump casing whereby removal of said fastening means andsaid suction cover permits removal of said impeller and said coverassembly through said one of said apertures and said shaft sealing meansthrough both of said apertures and whereby removal of said fasteningmeans permits removal of said impeller and said cover assembly throughthe other of said apertures.

1. The combination comprising: a pump casing defining a pumping chamberhaving an impeller positioned for rotation about an axis within saidchamber, said casing having a pair of axially aligned apertures openingto the exterior of said casing on opposite sides of said impeller andeach being of a size to permit removal of said impeller therethrough; aninlet and an outlet opening into said pumping chamber; a suction coverreleasably attached to said casing and closing one of said apertures; acover assembly closing the other of said apertures and both of saidapertures being of a diameter to permit passage therethrough of saidassembly; walls defining a shaft opening through said cover assembly;shaft sealing means connected to said cover assembly, aid sealing meansbeing of a size to permit passage thereof through said apertures; adrive shaft extending through said shaft opening and said shaft sealingmeans; means releasably connecting said pump impeller to said shaft forrotation therewith; and fastening means releasably supporting said coverassembly to said pump casing whereby removal of said fastening means andsaid suction cover permits removal of said impeller and said coverassembly through said one of said apertures and said shaft sealing meansthrough both of said apertures and whereby removal of said fasteningmeans permits removal of said impeller and said cover assembly throughthe other of said apertures.